Diazotype materials

ABSTRACT

Two-component diazotype sheet materials are described which form dense azo dye images and produce only slight bleeding and background coloration. The sheet material is coated with a conventional light-sensitive diazo compound and a coupling component of the formula   WHEREIN R is lower alkyl or lower hydroxyalkyl, R&#39;&#39; is hydrogen or lower alkyl, and X and X&#39;&#39; are hydrogen, halogen, lower alkyl, lower alkoxyl, sulfo or nitro.

{22 Filed:

[s 1 DIAZOTYPE MATERIALS [75] Inventor: Joseph K. Gogola, Rolling Meadows, Ill. I

[73] Assignee: Addresograph-Multigraph CorporatiomMount Prospect, 11].

Sept. 2, 1970 211 Appl. -No.: 69,167

[52] US. ..96/75, 96/49, 96/91 R,

' 260/619 R [51] Int. Cl. ..G03c 1/58 [58] Field'of Search .....96/49.75, 91

' [56] References Cited "UNITED STATES PATENTS 2,541,727 2/1951 Von Glahn et a1 ..96/91 R 3,294,533 12/1966 Sus et al..;...; ..96/91 R 2,679,498 5/ 1954 Seven et a] .96/91 R 2,063,631 12/1936 Schmidt et a1. ..96/91 R 2,593,839 4/1952 Buc ..96/91 R 2,542,566 2/1951 Pedlow et a1. ..96/91 R 2,940,852 6/1960 Herrick et al. ..96/91 R 3,039,872 6/1962 De Boer et al.... ..96/91 R 3,169,864 2/1965 Holmen ..96/91- R 3,248,220 van Rhijn ..96/91 R 14 1 Feb. 13, 1973 3 1970 Clecok ..l....96 91 R OTHER PUBLICATIONS Kosar, 1., Light-Sensitive Systems", Wiley & Sons,

1965, p. 224-231 relied on.

Primary Examiner-Charles L. Bowers, Jr. At10rney--Mason, Kolehmainen, Rathburn and Wyss [5 7] ABSTRACT wherein Ri s lower alkyl or lower hydroxyalkyl, R is hydrogen or lower alkyl, and X and X are hydrogen, halogen, lower alkyl, lower alkoxyl, sulfo or nitro.

5 Claims, No Drawings DIAZOTYPE MATERIALS BACKGROUND OF THE INVENTION and development, produces a dense dye image with minimal bleeding and background coloration.

Diazo reproduction process based processes light sensitive diazo compounds and their ability to form azo dyes with a coupling component under proper pH conditions are generally well known. The various techniques for carrying out the development include the moist or semi-moist process, the dry or ammonia process, and more recently the thermal process. The copying materials adapted for the moist process are referred to as'one-compon'ent materials since they contain only the light sensitive compounds and the coupling component is provided in a separate buffered developing solution and applied at the time of development. Diazotype materials developed in an atmosphere of water vapor and ammonia gas are generally referred to as two-component materials since they contain both the diazonium salt and the coupling component stabilized against premature coupling in an acidic medium. In the thermal systems heat is employed to release the I alkaline agents which are contained along with the diazonium salt and. the coupler on the copy material. Each of th'ese'systems provides a successful copying process but not without certain disadvantages that limit their utilitywhich would otherwise permit diazo copying to enjoy more widespread application as a reproduction medium.

Two-component materials have found wide use in the reproduction of engineering drawings. The process of developing with ammonia gas and water vapor is fast and essentially dry. Ammonia vapor readily penetrates into the'exposed copy sheet surface and permeates the light sensitive coating containing the acid stabilizers, shifting the pH of the coating to the alkaline side. Any excess of ammonia enhances the rate of reaction andvolatilizes from the copy sheet without leaving a residue. One of the major objections to-the use of ammonia in developing diazotype materials is the strong odor of ammonia in the copying area as well as the tendency for the odor to linger on the copies themselves. Installation of ammonia reproduction machines requires venting of the equipment to the outdoors to remove the toxic vapors. This limits the installation of the equipment to sites where the venting may be conveniently accomplished. The equipment is further complicated by the need for a gas developing chamber to contain the ammonia gas and water vapor and the other appurtenances required for feeding the developing ingredients to the chamber. The equipment, understandably, is not well suited for office installations.

The Parker U.S. Pat. No. 3,446,620 (May 27, 1969) has provided a system and procedure for developing two-component diazotype materials with controlled amounts of organic amines whereby an azo dye image is formed instantaneously and the copy that is produced isin a dry condition ready for use. The present invention provides an improved coupling component and diazotype materials containing such component which are adapted for use in the materials and methods of said Parker patent. Further, the couplers of this application in the environment of alkanolamines as the agents which are used to create the proper coupling environment demonstrate greater coupling speed than the couplers employed heretofore in two-component paper systems. This is seen with gaseous ammonia development (the conventional dry system) and the amine development, as in the Parker'patent.

It is apparent that most of the two-component diazo type materials now commercially available will .give better imagedensity, less bleeding and reduced background'coloration when a coupling component of the type described herein is substituted for one of the conventional couplers such as those disclosed in Parker U.S Pat. No. 3,446,620.

Giving consideration to the subject of developing two-component'diazotype materials in general, it is unstruck areas, thus creating a latentdiazo image in the unstruck areas.

It is an object of this invention to provide superior two-component diazotype materials.

It is a further object to provide two-component diazotype materials which produce dense dye images which resist bleeding and have minimal background coloration.

It is another object to provide two-component diazotype materials coated with a light-sensitive diazo compound and a bis-(2,4-dihydroxyphenyl)alkane coupling component.

Another object is to provide bis-(2,4-dihydroxyphenyl)alkane coupling components and methods of producing the same.

A further object is to provide methods of producing, using and developing two-component diazotype materials of the foregoing type.

Theseand other objects are apparent from and are achieved in accordance with the following disclosure.

DETAILED DESCRIPTION OF INVENTION have superior stability, visual density of dye image, and bleeding resistance and minimal background coloration. In the foregoing general formula, R- and R derstood that the reaction is a two-step process, name- I and the same or different halogen, lower alkyl, lower alkoxyl, s'ulfo, nitro and related radicals. Preferred is the 'coupler wherein X and X are hydrogen and R and R are methyl.

The following couplers are within the scope of this invention:

2,2-bis-(2,4dihydroxyphenyl)propane 2,2-bis-(2,4-dihydroxyphenyl)butane 2,2-bis-(2,4-dihydroxyphenyl)pentane 3,3-bis-(2,4-dihydroxyphenyl)pentane l, 1 -bis-( 2,4-dihydroxyphenyl )propane 2,2-bis-(2,4-dihydroxy--chlorophenyl)butane 2,2-bis-(2,4-dihydroxy-S-bromophenyl)butane 2,2-bis-(2,4-dihydroxy-5-bromophenyl)pentane 3,3-bis-(2,4-dihydroxy-5ethylphenyl)pentane 3,3-bis-(2,4dihydroxy5-ethoxyphenyl)pentane 2,2-bis-(2,4-dihydroxy-5-methylphenyl)propane 2,2-bis-(2,4-dihydroxy-S-nitr0phenyl)propane 2,2-bis-(2,4-dihydroxy-5-methoxyphenyl)hexane 2,2-bis-)2,4-dihydroxy-5-methoxyphenyl)-4-ethylhexane 2,2-bis-(2,4-dihydroxy-5-chlorophenyl)-4-methylpentane 2,2-bis-(2,4-dihydroxy#5-sulfophenyl)-4-methylpentane The diazo compounds of the diazotype materials of this invention can be any of the known heat-sensitive diazo compounds, such as those obtained by diazotization of the following amines:

p-amino-N,Ndiethylaniline p-amino-N-ethylaniline p-amino-N-ethyl-N-hydroxyethylaniline p-amino-N-methyl-N-hydroxyethylaniline p-amino-N,N-di-B-hydroxyethylaniline p-amino-m-ethoxy-N,N-diethylaniline p-amino-Nvethyl-o-toluidine p-amino-N-ethyl-m-toluidine p-amino-N,N-diethyl-m-toluidine p-amino-N-ethyl-N-B-hydroxyethyl-m-toluidine N-p-aminophenylmorpholine l-amino-2,5-diethoxy-4-morpholinobenzene p-amino-N,N-dimethylaniline o-amino-N,N-dimethylaniline o-amino-N,N-diethylaniline m-amino-N,N-dimethylaniline m-amino-N,N-diethylaniline p-amino-N-propylaniline p-amino-o-methylaniline p-amino-o-methoxyaniline p-amino-o-ethoxy-N,N-dimethylaniline Complexes of such diazonium salts with metal salts such as zinc chloride, zinc iodide, zinc bromide, cupric chloride, stannous chloride, cadmium chloride, magnesium chloride, and the like are usually preferred as diazo compounds.

One of the significant advantages of the couplers described above, over'couplers of similar structure, e.g., resorcinols, is that they give greater visual density to the azo dye images. By greater visual density is meant that reflectance measurements .taken with a reflectance densitom'eter will give values in the range of 0.9 to 1.2 density units. Greater visual density is desirable because it tends to give a final copy of greater contrast. Another advantage of greater densities arises from the use of the imaged diazotype copy as an original from which it is desired to generate other copies. In the latter situation the light sensitive coating is applied to a transparent film base of polyester (Mylar), cellulose acetate (Kodar), cellulose acetate butyrate,

cellulose acetate propionate and similar organic film. materials on which is created the azo dye image, by the developing techniques for two-component papers. It will be readily appreciated that the greater visual densities serve to prevent the transmission of radiant energy on any subsequent exposures when generating diazo reproductions. v

A still further advantage in using the intense azo dye image forming properties of the couplers of the instant invention is for the purpose of varying the shade of the azo dye image ultimately formed by combining it with other couplers.v g

The invention is disclosed in further detail by the following examples which illustrate typical materials and procedures. It will be apparent to those skilled in the art that numerous modifications may be made in these examples by substituting equivalent materials therein or varying operatingconditions or amounts of materials without departing from the invention as described.

EXAMPLE I 5 containing 2,2-bis-(2,4-dihydroxyphenyl)propane applied to a translucent paper substrate such as a percent rag content paper:

Ingredient Amount Water cc-30 ethanol do-60 Citric acid grams-2 Thiourea do-3 Zinc chloride do-S 2,2-Bis-(2,4-dihydroxyphenyl)propane d0-3 p-Diazo-N,N-diethylamline zinc chloride (Io-1.5 Ethylene glycol cc-4 Water to make 100 cc.

The 2,2-bis-(2,4-dihydroxyphenyl)propane was dissolved in the ethanol and added to the solution of the other ingredients in water. The resulting solution formed a sensitized diazo coating for sheet material. It can be applied to the 100 percent rag content paper, 20-pound basis weight 17 inches X 22 inches 500), in an amount of about 15 grams per square meter, by conventional air knife coating techniques. The light sensitive paper prepared in this example can be developed by either ammonia gas or by the application of controlled amounts of an alkanolamine and produces image densities in the range of 1.1 to 1.2 densitometer units. EXAMPLE 2 Diazotype sheets are made by coating a translucent paper substrate of 100% rag content with the following formulation:

Ingredient Amount Water cc.

Ethanol do 60 I Citric acid grams 2 Thiourea do 3 Zinc chloride do 5 2,2Bis-(2.4-dihydroxyphenyl)-4-metl' yl- 4-hydroxypentane do- 3 p-Diethylaminobenzenediazonium chloride zinc chloride do 1.5 5 Ethylene glycol CC Water to make 100 cc.

Its properties are similar to those of the material of Example 1.

EXAMPLE 3 This example is directed to' a diazotype material which produces a black azo dye image. The coupler of theinstant invention is utilized to produce an improved shade of black azo dye. It is incorporatedin the following coating solution:

Ingredient Amount Water cc 30 Ethanol do 60 Citric acid grams 2 Thiourea do 3 Zinc chloride do 5 2,3-Dihydroxy-6-naphthalenesulfonic acid (sodium salt) do 3 2,2-Bis-(2,4dihydroxyphenyl)propane do 1.5 Acetoacetanilide do 0.3 Diazo-N,N-diethylaniline do 1.5 thylene glycol cc 4 Water to make 100 cc.

The formulation is coated on a suitable paper substrate such as a direct process sulphite stock, 20-pound basis weight, using an air knife applicator for applying the sensitizing solution. The paper can be developed by the method describing U. S. Patent No. 3,446,620 or alternatively can be developed by the conventional ammonia gas system.

EXAMPLE 4 Sulphite stock paper as in Example 3, coated with the following formulation, produces an intense azo dye image:

In redient Amount ater cc 30 Ethanol do 60 Citric acid grams 2 Thiourea do 3 Zinc chloride do 5 Sodium 2,3-dihydroxynaphthalene- 6-sulfonate do 3 2,2-Bis-(2,4-dihydroxy-5-methylphenyl)propane do 1.5 Acetoacetanilide do 0.3

-Diethylaminobenzenediazonium chloride do 1.5 thylene glycol cc 1 Water to make 100 cc.

EXAMPLE 5 This example illustrates the preparation and application of a sensitizing solution to a polyester base support such as a 300-gauge thickness material sold under the .tradename Melinex X-503, available from the I.C.I. 0 America Incorporated. In preparing the polyester base toreceive the light-sensitive coating it was first coated with a 0.3mil coating of cellulose acetate butyrate. To the cellulose acetate butyrate-treated polyester was applied the following diazo sensitizing formulation: 55

Ingredient Amount Acetone cc 40 Methanol do 50 Sulfosalicylic acid grams l Thiourea do 0.5 Zinc chloride do 0.4 Acetoacetanilidc do 0.06 2,2-Bis-(2,4-dihydroxyphenyl)propane do 1.5 o-Toluidide of fl-hydroxynaphthoic acid do 0.5

p-Diazo-N,N-diethylaniline The'diazo sensitizing formulation was applied to the treated polyester basefby means of a meniscus band coater. When developed in an ammonia gas chamber the latent diazo image developed into an intense blueblack azo dye image.

EXAMPLE 6 The following is another example of a coating on a polyester base similar to the previous example with the exception that there was substituted for the sensitizing solution the following formulation:

Ingredient Amount Acetone cc 40 Methanol y do 50 Sulfosalicylic acid grams I Thiourea 7 do 0.5 Zinc chloride 7 7 do 0.4 2,Z-Bis-(T,4-dihydroxyphenyllpropane do 2,0

p-Diazo-NN-dimethylaniline The diazo formulation in solvent solution-was applied to the treated polyester base using a meniscus type band coater. The diazotype material coated with the above formulation when developed in an ammonia gas environment produced a sepia azo dye image. The diazotype material of this example can also .be developed with the application of alkanolamines and the incorporation of 'the couplers of the instant invention into theformulation produces azo dye images which are of intense visual density.

EXAMPLE? 'Sensitizing solutions for diazotype paper were produced with the following formulas:

Water to make 100 cc.

EXAMPLE 8 2,2-Bis-(2,4-dihydroxyphenyl)propane is synthesized as follows: 165 grams of resorcinol is added to 600 cc. of dilute ice-cold hydrochloric acid (120 cc. of concentrated hydrochloric acid and 480 cc. of water). To this cold solution is added 26 g. of acetone dropwise with stirring. After 6 hours at 10 C. the solution is allowed to warm to room temperature overnight. After standing for 20-30 hours, the precipitate of crystals of 2,2-bis-(2,4-dihydroxyphenyl)propane is removed and dried.

2,2-Bis-(2,4-dihydroxyphenyl)butane is made in the same way by substituting 35 g. of methyl ethyl ketone for the acetone.

2,2-Bis (2,4-dihydroxyphenyl)-4-methylpentane is produced by a similar procedure wherein 50 g. of methyl isobutyl ketone replaces the acetone.

2,2-Bis-(2,4-dihydroxy-5-chlorophenyl)propane can be synthesized by the foregoing method from 220 g. of 4-chlororesorcinol in lieu of 165 g. of resorcinol, the other reagents being the same.

2,2-Bis-(2,4dihydroxy-5-methyl)phenylbutane is produced by the foregoing method from 200 g. of 4- methylresorcinol, 40 g. of acetone, 120 cc. of concentrated hydrochloric acid and 480 cc. of water.

I claim:

1. A two component diazotype material, capable of producing a dense azo dye image without substantial wherein R is hydrogen or a lower alkyl radical, R is a lower hydroxyalkyl-radical, X and X are hydrogen,

halogen, lower alkyl, lower alkoi'ry, sulfo or nitro groups with the proviso that X and X always represent the same radical, and wherein the sum of the number of carbon atoms in R and R is at least three, and an acidic stabilizer.

2. A diazotype material as defined by claim I wherein R is a lower alkyl radical.

3. A diazotype material as defined by claim 2 wherein X and X are hydrogen.

4. A diazotype material as defined by claim 3 wherein the total number of carbon atoms in R and R is between three and eight.

5. A diazotype material as defined by claiin 4 wherein R is methyl and R is 2-hydroxy-2-methylpr py 

1. A two component diazotype material, capable of producing a dense azo dye image without substantial bleeding and background coloration, comprising a substrate of sheet or web material with a coating applied thereto containing a light-sensitive diazonium compound, a coupling component of the formula wherein R is hydrogen or a lower alkyl radical, R'' is a lower hydroxyalkyl radical, X and X'' are hydrogen, halogen, lower alkyl, lower alkoxy, sulfo or nitro groups with the proviso that X and X'' always represent the same radical, and wherein the sum of the number of carbon atoms in R and R'' is at least three, and an acidic stabilizer.
 2. A diazotype material as defined by claim 1 wherein R is a lower alkyl radical.
 3. A diazotype material as defined by claim 2 wherein X and X'' are hydrogen.
 4. A diazotype material as defined by claim 3 wherein the total number of carbon atoms in R and R'' is between three and eight. 